Answer:
The mass percent of aluminum sulfate in the sample is 16.18%.
Explanation:
Mass of the sample = 1.45 g

Mass of the precipitate = 0.107 g
Moles of aluminum hydroxide = 
According to reaction, 2 moles of aluminum hydroxide is obtained from 1 mole of aluminum sulfate .
Then 0.001372 moles of aluminum hydroxide will be obtained from:

Mass of 0.000686 moles of aluminum sulfate :
= 0.000686 mol × 342 g/mol = 0.2346 g
The mass percent of aluminum sulfate in the sample:

In a chemical reaction, the equilibrium constant refers to the value of its reaction quotient at chemical equilibrium, that is, a condition attained by a dynamic chemical system after adequate time has passed, and at which its composition has no measurable capacity to undergo any kind of further modification.
The given reaction is: HCN (aq) + OH⁻ = CN⁻ (aq) + H2O (l)
The equilibrium constant = product of concentration of products / product of concentration of reactants
(Here, H2O is not considered as its concentration is very high)
So, Keq = [CN⁻] / [HCN] [OH⁻]
An investigator can collect hairs they observe visually (with tweezers or by hand), and they can also use clear tape to lift non-visible hair from a variety of surfaces, such as clothing. Other methods of hair sample collection include combing and clipping methods.
However, Duncan has prepared ramen noodles so many times he does not need to measure the water carefully. If he happens to heat 0.850 ...